Helaman 6:11

And behold, there was all manner of gold in both these lands, and of silver, and of precious ore of every kind; and there was also curious workmen, which did work all kinds of ore, and did refine it; and thus they did become rich.

There was all kinds of gold in both lands. There was silver and precious metal of every kind. There were skilled workers who worked with all kinds of metal and made it pure. This is how they became rich.

Both lands had gold, silver, and valuable ore of every type. Skilled craftsmen worked these materials and refined them. This made the people rich.